Piston ring



-- E; G. MALPAS 2,187,979

Jan. 23, 1940.

PIs'roN 1mm Filed fla 23, 1938 G. M B w B Patented Jan. 23, 1940 x v UNITED STATES PATENT OFFICE.

PISTON RING Ellis G. Malpas, Muskegon, Mioh., assignor to ScaledPower Corporation, Muskegon, Mich., a corporation of Michigan Application May 28, 1938, Serial No. 209,494

2 Claims. (CL 309-44) This invention relates to piston rings and is may be of brass or copper or of a combination of primarily concerned with a novel method of metals forming a suitable alloy, but preferably applying a wearing and sealing ring of a different softer than the cast iron of the piston ring and and softer composition than the material of the also having an inherent springiness, which quality 5 piston ring itself to and in a groove in the piston causes it to tend to return to its initial position 5 ring, said groove being located around the outer when deformed or stressed out of such position. peripheral portions of the piston rings and be- Such sealing member inserted in the groove of the tween its opposed flat sides. It'is another object piston ring I is sprung or flattenedin order to and purpose of the invention to provide a novel conform to the width of the groove and to bring v piston ring which in its complete form will have the highest points of the elevations 3 and the 10 the sealing ring within said groove frictionally lowest points of the depressions 4 closer together held in place against displacement and with narthan they are normally when free of the ring. row recesses between sections of said sealing ring Thus the upper portions of the elevations 3 and and the walls of the groove, capable of retaining the lower parts of the depressions 4 will bear with oil to assist in lubrication. considerable force against the opposite walls of 15 An understanding of the invention, and of the the groove in which the sealing member is located objects and purposes thereof and of the funcand with a frictional force and resistance to relations obtained thereby, may be had from the foltive movement of the sealing member to the pislowing description, taken in connection with the ton ring I such that the sealing member is firmly accompanying drawing, in which: held against change of position in the groove. 20

Fig. l is a perspective view of a piston ring in The spaces 5 between walls of the groove and the accordance with my invention. bends in the sealing member 2 are shown in con- Fig'. 2 is a perspective view of the sealing memsiderably exaggerated form in the drawing, but her which is used. there are such spaces alternately at the upper and Fig. 3 is an enlarged fragmentary elevation of lower sides of the sealing member between such 25 the ring shown in Fig. 1. sealing member and the walls of the groove in Fig. 4 is a transverse section therethrough. the ring I. In such spaces or recesses lubricating Fig, 5 is a similar transverse section showing a oil may collect and be retained, which aids in slight modification in structure, and lubricating the piston in its reciprocatory move- Fig. 6 is a similar cross section illustrating the ments in an engine cylinder, 30 use of a plurality of said sealing members in the While I have shown the ends of the sealin groove. member 2 coming to the parting in the piston ring,

Like reference characters refer to like parts in it is of course to be understood that various modithe different figures of the drawing. fications as to the ends of the sealing member and The piston ring I is of conventional structure the parting may be resorted to without depart- 35 so far as being parted at one side, made from a. ing from the present invention. The ends of the single individual ring casting, preferably of cast sealing member in no case should extend beyond iron material, and with the cross section of the the ends of the ring I at the parting. If such ring substantially uniform throughout. Around J ends of the sealing member terminate a short 40 this ring in its outer curved side a groove is cut distance from the ends of the ring at the parting 40 preferably substantially midway between the it will not be disadvantageous. Also the groove upper and lower flat sides of the ring. Within in which the sealing memberis located does not this groove the sealing member is adapted to be necessarily have to continue to the extreme ends received and maintained. Said member, indiof the ring at th p ing but can'bc st p hflrt cated at 2, comprises a length of flat material of such ends of the ring and the sealing member which is formed in succession with alternate elecorrespondingly shortened.

vations and depressions 3 and l. In other words, The sealing member 2 is forced or pressed into the sealing ring is of what may be termed a wavy the groove of the ring I and may have its periphform. Before the ring is placed in the groove the eral portions project a short distance, a few thoudistance between the highest point of an elevation sandths of an inch beyond the curved surface 50 3 and the lowest point of adepression 4 is greater of the ring, as shown in Fig. 5. .And in this than the width of the groove in the piston ring. form the outer surface portions of the sealing The material from which the sealing member 2 member 2 would be the first to bear against the is made is softer than that of the cast iron walls of the cylinder and in a short time wear material which is used for the piston ring I. It down flush with the outer curved surface of the 55 rings.

ring. Of course also the sealing member may be inserted the groove of the ring I prior to the finishing machining operation at the outer curved surface of the ring and both the ring I and the sealing member simultaneously machined so that their outer suri aces are flush with each other as in Fig. 4. instead of the sealing member projecting from the ring as in Fig. 5. Both forms of ring are contemplated by my invention and either is a matter of choice with the manufacturer or the customer who orders the piston In Fig. 6 a plurality of the sealing members 2a are shown in the groove in the ring 3, said sealing members being of the wavy form and nesting one against the other. It is further to be understood that the sharp corners between the outer ctu'ved suriace of the ring I and the walls of the groove in said ring may be rounded or. chamfered for an .easier entrance of the sealing member into the groove.

In applying the sealing member to the groove it is forced radially inward into the groove by pressure with a flattening of the wavy formed sealing member so that the sealing member may be readily forced into the groove. Under its tendency .to return to its original less flat form, a very considerable pressure is exerted by the raises and depressions 3 and 4 of the sealing member against the walls of the groove so as in effeet to produce a secure binding engagement and a fit similar to a press fit between the sealing member and the ring groove at the places of contact of said member 2 with the walls of the groove. The oil collecting and retaining spaces at 5 are of value in that the oil collected therein is an aid in lubricating the piston rings operating against the walls of the cylinder. The construc tion while relatively simple is very practical and useful.

The invention is defined in the appended claims and is to be considered comprehensive of all forms of structure coming within theirscope.

I claim:

1; A piston ring comprising. a ring member of cast iron of substantially uniform cross section having a substantially continuous groove in its outer curved side, and a sealing member of softer material located in said groove, said sealing member being of a wavy form with alternate elevations and depressions in its length with the highest points of said elevations and lowest points of the depressions engaging opposite sides of the groove'at spaced apart points, and the sealing member being retained in the groove by pressure of said rises and depressions against the wall of the groove.

' 2. A piston ring comprising, a ring member of cast iron having a substantially continuous groove in its outer curved side, and a sealing member of resilient softer material than the cast iron located in said groove, said sealing member being of less width than the width of the groove and having alternate elevations and depressions in its length, the highest points of said elevations and the lowest points of the depressions engaging opposite sides of the groove at spaced apart points and bearing against said sides of the groove with pressure to thereby retain the sealing member in said groove.

ELLIS G. MALPAS. 

